| 초록 |
Most radiation of the human body belongs to the long-wavelength infrared region (mainly at the wavelength of 10-12 μm) which allows IR sensors to distinguish human or animal in darkness. One of important components of the IR sensors is the IR window which requires the high transparency in the long-wavelength infrared region. In this study, we report the development of ZnS powder for the IR window materials. We chose a mechano-chemical synthesis for the preparation of ZnS powders using only the elemental precursors, Zn and S. Several parameters such as milling materials and periods were optimized to obtain the ZnS powder in high elemental and phase purity with ultra-fine size. In addition, the current mechano-chemical method provides several advantages such as cost efficiency, environmental friendliness, and high throughput for the fabrication of the IR window. And additive-free and LiF/CaF2-doped ZnS windows were successfully fabricated by spark plasma sintering at a low temperature (920 ℃) using LiF and CaF2 as a sintering additive. This study indicates the possibility to sinter IR transparent ZnS by SPS at lower sintering temperature and in short times with high density and a high transmission in infrared region 10-12 μm. And we confirmed that LiF and CaF2 improve sintering behavior and transmission at low sintering temperature. |
